Plasma discharge is used in gas excitation for generating active gas containing ions, free radicals, atoms, and molecules. The active gas is widely used in various fields and representatively variously used in a semiconductor manufacturing process, for example, etching, deposition, washing, ashing, and the like.
A remote plasma generator is a device that generates plasma outside a process chamber to remotely supply the generated plasma to the process chamber. A representative semiconductor manufacturing process using the remote plasma generator includes, for example, a washing process for washing the inside of the process chamber and an ashing process for removing a photoresist film deposited on a substrate to be treated. In addition, the remote plasma generator is used even in various other semiconductor manufacturing processes.
In the semiconductor manufacturing process, maintenance efficiency of process equipment is one of the very important elements in terms of productivity and cost. In general, in the case of maintenance of the process equipment, an equipment use time when the equipment normally operates is calculated in advance to periodically maintain the equipment after using the equipment for a predetermined time. Even in the case of the remote plasma generator, after the remote plasma generator is used for a predetermined time, maintenance such as replacement of a time-worn part or replacement of the equipment itself is required. The maintenance may be required even for another reason. For example, after a substrate treatment process is completed, when a problem occurs in a treatment result thereof, it may be recognized that the maintenance of the equipment is required.
However, when the necessity of the maintenance of the equipment is recognized by sensing a treatment error, unnecessary production cost may be generated with deterioration in productivity. Further, if the equipment is normally usable even when the equipment is periodically maintained after being used for a predetermined time, unnecessary cost may be generated. Therefore, most preferably, a maintenance time of the equipment is, in advance, predicted by determining an operating state of the equipment in real time to cope with the problem before the problem occurs in the process.
While the plasma generated from the remote plasma generator is supplied to the process chamber to perform the plasma treatment process, appropriate monitoring of the operating state of the remote plasma generator and the plasma treatment process is required. However, since the remote plasma generator so far may not provide appropriate information on an equipment state and a process progress state, it is very difficult to execute the maintenance at an appropriate time. Therefore, it is necessary that a process manager can immediately cope with problems, which occur while the process is in progress, by monitoring the operating state of the remote plasma generator and the plasma treatment process in real time and sensing the problems in real time while the remote plasma generator is connection with the process chamber and operates.